Anticonvulsant activity of the NMDA antagonists, D(-)4-(3-phosphonopropyl) piperazine-2-carboxylic acid (D-CPP) and D(-)(E)-4-(3-phosphonoprop-2-enyl) piperazine-2-carboxylic acid (D-CPPene) in a rodent and a primate model of reflex epilepsy.
D-(-)4-(3-phosphonopropyl)piperazine-2-carboxylic acid (D-CPP) and its unsaturated analogue (D(-)(E)-4-(3-phosphonoprop-2-enyl) piperazine-2-carboxylic acid (D-CPPene) have been administered to DBA/2 mice (intracerebroventricularly, i.c.v., intraperitoneally, i.p., and orally, p.o.) and to photosensitive baboons, Papio papio (intravenously, i.v., and orally), and their effects on reflexly induced epileptic responses assessed. In DBA/2 mice the clonic phase of the seizure response to sound is suppressed by D-CPP with an ED50 of 5.5 micrograms/mouse, i.c.v.; 0.69 mg (2.75 mumol)/kg i.p. and 16.6 mg (65.8 mumol)/kg p.o. compared with, for D-CPPene, 2.2 micrograms/mouse i.c.v., 0.41 mg (1.54 mumol)/kg i.p. and 10.8 mg (40.2 mumol)/kg, p.o. In Papio papio myoclonic responses to stroboscopic stimulation are suppressed 24 and 48 h after D-CPP 32 mg (127 mumol)/kg p.o. Administration of D-CPPene 8-16 mg (30-60 mumol)/kg i.v. produces protection against myoclonic responses after 1-2 h, lasting for 48 h. Oral administration of D-CPPene 32-64 mg (119-239 mumol)/kg produces protection beginning after 4 h and sustained for 48 h. Measurements of plasma D-CPPene concentration show rapid clearance after i.v. injection and a low plasma concentration 1.5-5 h after oral administration. The prolonged anticonvulsant action of D-CPP and D-CPPene following oral administration suggests that these compounds merit evaluation as antiepileptic therapy in man.
Patel
S
S
Department of Neurology, Institute of Psychiatry, Denmark Hill, London.
Chapman
A G
AG
Graham
J L
JL
Meldrum
B S
BS
Frey
P
P
D000161:Acoustic Stimulation; D000818:Animals; D000927:Anticonvulsants / Q000494:pharmacology*; D004827:Epilepsy / Q000503:physiopathology*; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D016202:N-Methylaspartate / Q000037:antagonists & inhibitors*; D009943:Organophosphorus Compounds / Q000097:blood / Q000494:pharmacology*; D010215:Papio; D010775:Photic Stimulation; D010879:Piperazines / Q000097:blood / Q000494:pharmacology*; D012399:Rotation
D000927:Anticonvulsants; D009943:Organophosphorus Compounds; D010879:Piperazines; C065286:SDZ EAA 494; D016202:N-Methylaspartate; C050592:3-(2-carboxypiperazin-4-yl)propyl-1-phosphonic acid